Over the last 50 years, hair restoration has progressed to improve the surgical techniques and refine hair transplantation as a whole. This is due to the scientific research conducted, looking through the physical and chemical properties of hair.

Using the most advanced technology in microscopes, scientists are discovering a detailed look into the complex structure of hair and the properties that separate hair into three ethnic categories; African, Asian and Caucasian. The ethnic category of your hair can be considered in hair transplantation.

Under a low-powered microscope, a piece of human hair is shown to have an outer layer of flat scales which point outwards from root to tip. These scales are called cuticles and are made up of keratin, a form of protein which can be found in the skin, fingernails and toenails. The major function of the cuticle is to protect the inner tissue called the cortex, where hair growth occurs.

Ethnic differences in hair can also be seen through a low-powered microscope. From a cross-section view of hair in their ethnic category, we can see that Asian hair is more circular in diameter, while African hair is more oval in shape. Caucasian hair appears as an intermediate between the other two categories.

In terms of shape, lengthwise, African hair is irregular in curling and twisting of the hair which is the complete opposite of Asian Hair which is straight and have no irregularities. The irregularities of African hair can have positive and negative implications for hair restoration surgery because African hair emerges from the scalp in different angles and directions. This curling of the hair allows more coverage of the scalp using fewer hair follicles, however extracting African hair is more difficult for a specialist to harvest. Caucasian hair tends to generally be straight with some irregularities.

A microscopic view inside the hair shaft.

The cuticle layer of hair acts to protect the cortex layer underneath. It is the cortex layer that gives hair fibre its shape, resilience and cosmetic attributes. A microscopic view of the cortex, lengthwise, shows that the cortex is packed together with cortical cells from root to tip. A microscopic view of the cortex in a cross-section examination is like looking at an electric cable with hundreds of wires packed closely together. The cortical cells are packed with fine macro- and micro fibrils. The way that cortical cells are packed is a major contribution to the shape of ethnic hair.